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在数列an中,a1=1,an+1+an=6n.则a17=
人气:226 ℃ 时间:2020-09-21 09:52:31
解答
a(n+1)+an=6na(n+1) + k1(n+1) + k2 = -(an+k1n+k2)-2k1=6k1=-3-2k2-k1=0-2k2+3=0k2= 3/2a(n+1)+an=6na(n+1) -3(n+1) +3/2 = -(an -3n + 3/2)[a(n+1) -3(n+1) +3/2]/(an -3n + 3/2) = -1(an -3n + 3/2)/(a1-3/2) = (...
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